1. Field of the Invention
The present invention relates to an ultrasound unit having an ultrasound element and an ultrasound endoscope including the ultrasound unit.
2. Description of the Related Art
An ultrasound endoscope can clearly visualize a wall of a digestive tract, a deep organ, or the like with good image quality free of influence of gas or a bone in a body. In an electron scanning type ultrasound endoscope, an ultrasound unit having an ultrasound array is disposed at a distal end portion. The ultrasound array is constructed by coupling longer sides of a plurality of ultrasound elements, each of which has a first principal surface that is elongated and rectangular. In each ultrasound element, a transmitting and receiving portion, a signal electrode terminal for transmitting and receiving a signal, and a ground electrode terminal at a ground potential are arranged in a longer side direction.
One signal line (coaxial cable core wire) is connected to the signal electrode terminal of each ultrasound element by, e.g., soldering, and one ground line (coaxial cable shielding wire) is connected to the ground electrode terminal.
A specification of Japanese Patent No. 4377787 discloses a transducer which connects an ultrasound array and coaxial cables by using a hollow cylindrical member having a relay electrode. In the transducer, electrode terminals of ultrasound elements and relay electrode terminals are connected with wires, and the coaxial cables are connected to the relay electrode terminals.